Francis solicited a round of applause from the faithful in St Peter's Square and urged people everywhere to reach out to older generations.

Francis was supposed to have led a celebration Mass for grandparents in St Peter's Cathedral earlier in the day, but left the duty to Archbishop Rino Fisichella, three weeks after the pontiff emerged from the hospital after major intestinal surgery.

“Grandparents and grandchildren, the elderly and youth together showed one of the beautiful sides of the Church, and showed the alliance between the generations,'' the pontiff said in off-the-cuff remarks from a window overlooking St Peter's Square.

“To celebrate this day, I invite celebration in every community with visits to grandparents and elderly, those who are most alone, to bring them my message, inspired by Jesus: I am with you every day.''

He said just as the elderly need young people, young people need the elderly, “especially in this throw-away culture.”The grandparents have the sap of history, that rises and gives strength for the tree to grow,'' Francis said.

If young people and elderly don't meet and talk, “history does not go on, life does not go on. We need to resume this: It is a challenge for our culture.

Grandparents have the right to dream while watching young people, and young people have the right to prophecy by taking sap from grandparents,'' he said.

During the traditional Sunday noon blessing, the pope also remembered victims of flooding in China and offered his blessing to the Tokyo Olympics.